1. Field of the Invention
This invention relates to motor actuated bells of the type in which a motor drives a hammer means through a cam means to allow the same to strike against an associated gong to produce bell sound.
2. Prior Art
One conventional motor actuated bell, as shown in FIG. 20, comprises a small DC motor 100 having a drive shaft 101 on which a gear 102 is fixedly mounted, a wheel gear 103 fixedly mounted on a shft 104 and engaging the gear 102, and a cam 105 mounted on the shaft 104. With this construction, the motor 100 is driven to rotate the cam 105 through the meshed gears 102, 103 so that the cam intermittently acts on the end of a hammer 106 to allow the same to strike against an associated gong against the bias of a coil spring 107 to produce bell sound. This known motor driven bell has been found not entirely satisfactory in durability. This difficulty arises out of the fact that the axis of the shaft 104 which serves as the axis of rotation of the cam 105 is disposed perpendicular to the axis of the hammer 106 along which the hammer is moved. As a result, the shaft 104 is subjected to substantial lateral forces when the cam 105 strikes the hammer 106 so that associated bearing member (not shown) for the shaft 104 is also subjected to considerable forces. This gives rise to damage to the bearing members. Where the cam 105 is directly mounted on the motor drive shaft 101 for acting on the end of the hammer 106, the drive shaft 101 is also subjected to substantial lateral forces. This prevents the motor 100 from functioning properly for a prolonged period of time.